1. Field of the Invention
The present invention relates generally to reaction type internal combustion engines, and more specifically to a jet engine incorporating compressor, combustion, and compressor airflow entrainment means, but which incorporates no turbines or other moving parts, except for the fuel pump.
2. Description of Related Art
Internal combustion reaction type engines embodying various principles of jet engines have been known for a considerable period of time. Such engines of the prior art may be generally categorized as ram jet engines with no internal moving parts, pulse jet engines with oscillating inlet vanes, and turbojet engines with rotating compressor and turbine sections.
The turbojet engine was developed relatively recently in the history of internal combustion engines, being used operationally only toward the end of World War II. This is primarily due to the extremely high temperatures and rotational speeds attained by the exhaust turbine(s) within the engine, with revolutions per minute (rpm) generally reaching a few tens of thousands of rpm. As a result, the metallurgy and manufacturing tolerances required for turbojet engines are quite demanding and costly. Moreover, “hot” section inspections of the combustion and exhaust turbine sections are relatively frequent, due to the extremely high temperatures attained in those areas of the engine and the high centrifugal forces encountered by the exhaust turbine as it rotates at tens of thousands of rpm. However, turbojets have proven to be more efficient than other forms of internal combustion reaction engines, and as a result are nearly universally used where jet propulsion is required.
The desirability of a simpler form of jet engine is evident, after considering the limitations and expense of turbojet engines. A simpler form of jet engine is the pulsejet, which uses a series of oscillating vanes at the inlet end of the engine. Pulse jet engines have also been known for quite some time, with pulsejets being used as model aircraft jet engines and in some unpiloted aircraft. The pulse jet principle eliminates the rapidly rotating compressor and exhaust turbines, but the inlet vanes are prone to damage and the life span of the typical pulse jet is unlikely to exceed several hours at a maximum. Moreover, pulsejets are relatively inefficient and burn considerably more fuel than turbojets for an equivalent amount of thrust, and generally require an external source of pressurized air for starting.
The ramjet, with its lack of moving parts, provides a solution to the problem of rapidly rotating or oscillating components. However, the ramjet has other limitations which do not exist with turbojets and pulsejets. The ramjet relies upon the internal pressure differential produced by the shock wave developed within the engine as air passes from supersonic to subsonic flow. This is achieved by carefully shaped and contoured venturis within the engine, which accelerate and decelerate the airflow as desired. The result is an engine which is capable of producing practicable amounts of thrust with no moving parts. However, ramjet engines cannot operate at zero ambient airflow velocity. They require some airflow velocity before the air flowing through the engine can reach the velocities required for the engine to function. As a result, ramjet engines require some other engine principle (usually a rocket, with unmanned aircraft) to provide the initial acceleration and velocity for operation.
Consideration of the above engine principles and their corresponding limitations leads to the realization that an engine featuring the structural simplicity of the ramjet with its lack of moving parts, along with the relative efficiencies of the turbojet and its ability to operate at zero ambient airspeed, would be a most desirable development. The present turbineless jet engine responds to this need, by providing a reaction engine having a series of inlet vanes which emulate the compressor section of a conventional turbojet engine, with the inlet and compression section of the present turbineless engine feeding the compressed air to a combustion or burner section. Most of the heated exhaust air passes rearwardly through the engine to produce thrust, with a relatively small percentage passing back through the engine to the inlet and compressor section to entrain incoming airflow, thereby continuing the process.
The only moving component required in the present turbineless engine, is an internal fuel pump turbine. The fuel pump turbine itself is operated by relatively high pressure exhaust gas from the combustion section of the engine once the engine is in operation, thereby eliminating the need for electrical and/or other power for the engine, except during the starting procedure.
A discussion of the related art of which the present inventor is aware, and its differences and distinctions from the present invention, is provided below.
U.S. Pat. No. 3,188,804 issued on Jun. 15, 1965 to John A. Melenric, titled “Turbo Supercharged Valveless Pulse Jet Engine,” describes an engine combination having a central turbojet engine which provides some compressed airflow to a series of valveless reaction engines disposed in an annular array about the turbojet engine. The valveless engines are described as utilizing an intermittent combustion principle (as opposed to the continuous combustion used in the present engine), but Melenric does not disclose any form of oscillating inlet control vanes for his annular engines. In any event, the use of a rotating turbine to drive a rotating compressor in the central turbojet engine, results in the Melenric engine more closely resembling a conventional turbojet engine than it does the present engine.
U.S. Pat. No. 3,323,304 issued on Jun. 6, 1967 to Andres F. Llobet et al., titled “Apparatus For Producing High Temperature Gaseous Stream,” describes a turbineless engine which utilizes a series of concentric venturis to control the flow of gases through the engine. Heat exchanger tubes are also included within the engine. The Llobet et al. engine requires a pressurized source of gaseous fuel (e.g., propane, etc.), at least for starting. Llobet et al. also describe the use of a liquid fuel mixed with water, with the water being broken down into its chemical elements and recombined with other elements to produce heat and thrust. The structure of the Llobet et al. engine is annular, with no radially disposed louvered pressure generator airflow guides, as provided by the present turbineless engine. Moreover, Llobet et al. make no disclosure of any non-circular cross section for their turbineless engine.
U.S. Pat. No. 3,517,510 issued on Jun. 30, 1970 to John A. Melenric, titled “Self-Starting Valveless Resonant Pulse-Jet Engine And Method,” describes an engine having a series of annular valveless engines which operate on a pulse principle. Exhaust is fed into a central collector, where most of the exhaust thrust is generated. The engine of the Melenric '510 U.S. patent requires a pressurized gaseous fuel, with power being determined by the mix of gaseous vs. liquid fuel selected from the pressurized tank. The present engine is configured to operate using a more conventional fuel. No radially disposed pressure generator airflow guides are disclosed in the Melenric '510 U.S. patent, as provided in the present turbineless jet engine invention. Moreover, no disclosure is made of an engine having other than a circular or annular configuration, in the Melenric '510 patent.
U.S. Pat. No. 3,750,400 issued to Thomas H. Sharpe on Aug. 7, 1973, titled “Self-Starting Air Flow Inducing Reaction Motor,” describes an engine having only a single moving mechanism, i.e., an inlet diffuser cone. The inlet cone translates forwardly and rearwardly depending upon dynamic pressure, and moves the attached fuel injector assembly correspondingly. The fuel injector system entrains airflow into a convergent-divergent inlet duct, with the fuel and air mixing and igniting in the combustion section downstream of the inlet. The engine of the Sharpe '400 U.S. patent also requires a relatively high energy consuming preheating assembly for its operation, which feature is not required of the engine of the present invention. The engine of the Sharpe '400 U.S. patent is more closely related to the ramjet principle of operation. No radially segmented, louvered pressure generator airflow guides are provided in the engine of the Sharpe '400 U.S. patent.
U.S. Pat. No. 3,800,529 issued on Apr. 2, 1974 to Thomas H. Sharpe, titled “Self-Starting Series Jet Engine With Throttling Assemblies,” is a continuation-in-part of the '400 U.S. patent to the same inventor, discussed immediately above. FIGS. 6A and 6B are identical in the '400 and '529 U.S. patents, with other structure and operating principles being closely related between the two.
U.S. Pat. No. 3,800,531 issued on Apr. 2, 1974 to Thomas H. Sharpe, titled “Self-Starting Annular Jet Engine With Plural Burner And Bypass Duct,” is another continuation-in-part of the '400 U.S. patent to the same inventor, discussed further above. The Sharpe '531 U.S. patent is primarily directed to the embodiment of FIGS. 8A and 8B of the '400 U.S. patent. As in the other patents issued to the same inventor noted above, no radially segmented, louvered pressure generator airflow guides are disclosed in the '531 U.S. patent.
U.S. Pat. No. 3,841,090 issued on Oct. 15, 1974 to Thomas H. Sharpe, titled “Jet Engine Method,” is a divisional patent of the '400 U.S. patent, discussed further above. The Sharpe '090 U.S. patent is directed to the method of operation of the various embodiments or engine variations disclosed in the various patents to the same inventor, discussed above. The same points of distinction noted between those patents and the present invention, are seen to apply here as well.
U.S. Pat. No. 4,085,585 issued on Apr. 25, 1978 to Thomas H. Sharpe, titled “Impaction/Induction Jet Engine,”describes a turbineless jet engine configuration which superficially resembles the engine of the present invention. However, a considerable number of differences exist between the engine of the earlier '585 U.S. patent and the engine of the present invention by the same inventor. First, and most obviously, the engine of the '585 U.S. patent includes a series of radially disposed exhaust capture vanes, which capture a portion of the exhaust and route it forward to entrain incoming airflow. The present engine does not require these exhaust capture vanes. Second, the engine of the '585 U.S. patent incorporates relatively costly conventional burner cans in the combustion area. The present engine utilizes a concentric annular ring of combustion venturis, with each having an upstream starting fuel injector and a downstream run fuel injector. Third, the engine of the '585 U.S. patent has a relatively small central exhaust gas return duct. The diameter of the exhaust gas return duct of the engine of the present invention is much larger proportionally to the cross sectional area of the engine, preferably on the order of about thirty percent of the engine diameter or width at the combustion section. Fourth, the present engine incorporates “flame holders” or deflectors and fuel deflectors to break up the fuel stream from the start fuel injectors. Finally, the engine of the present invention may incorporate rearwardly (or forwardly) swept louvered inlet pressure generators and different cross-sectional shapes, which features are not disclosed by the present inventor in any of his earlier issued patents, nor in any of the related art known to the present inventor.
U.S. Pat. No. 4,118,929 issued on Oct. 10, 1978 to Thomas H. Sharpe, titled “Impaction Augmented Jet Engine,” is another continuation-in-part of the '400 U.S. patent to the same inventor discussed further above, through a chain of abandoned continuation applications. The same points noted further above regarding the engines of the '929 and '400 U.S. patents to the same inventor, are seen to apply here as well.
U.S. Pat. No. 4,267,694 issued on May 19, 1981 to Thomas H. Sharpe, titled “Staged Induction Engine,” describes a turbineless jet engine configuration which is essentially “inside-out” from the present engine configuration. The engine disclosed in the '694 U.S. patent has a single, centrally located burner can which exhausts through a series of axially central, concentric ducts. These ducts deliver some percentage of the exhaust flow to a series of peripherally located ducts, which route the exhaust flow forward to a series of intake vanes at the front of the engine. The exhaust flow, along with the centrally located fuel injectors, entrains incoming air to the engine for operation. The intake vanes direct the exhaust flow and entrained intake air radially inwardly to the central burner can. The present engine utilizes a peripherally disposed combustion area, with a single, centrally located exhaust gas recirculation passage.
U.S. Pat. No. 4,962,641 issued on Oct. 16, 1990 to John N. Ghougasian, titled “Pulse Jet Engine,” describes a vaneless pulsejet using a resonator chamber to fill and discharge a portion of the exhaust gas by oscillation. The pulsating exhaust gas pressure affects the incoming airflow, producing pressure pulses for a series of closely spaced combustion events. The Ghougasian engine apparently requires some form of compressed air for starting, as in conventional pulsejets, but unlike the present turbineless engine. The present engine is not a pulsejet, but rather is a continuous combustion engine with stable internal pressures and temperatures at any given location within the engine, for a given set of operating parameters.
Finally, U.S. Pat. No. 5,189,875 issued on Mar. 2, 1993 to John A. Melenric, titled “Self Starting Valved Pulse Jet,”describes an engine configuration related to the engines of the '804 and '510 U.S. patents to the same inventor, discussed further above. As in those engines, the engine of the Melenric '875 patent uses a pressurized fuel, e.g. propane or the like, and also utilizes a pulse valve system to control combustion after the initial startup phase, unlike the present turbineless engine.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.